Assortative Mating
by Aisling-Siobhan
Summary: Frostiron Month 08: They can keep up with one another. They are practically the same person split between two bodies. That's why they love one another. (But they hate each other too, because sometimes they hate themselves).


This is for the Frostiron Month Tumblr: Prompt 8.

July 22-24: Kinks: _What do you love or turns you on the most with these two?_

"**Assortative Mating"**

**Disclaimer:** The Avengers, Tony, Loki, etc belong to Marvel, Stan Lee, et co. I make no money from this and own nothing, don't sue.

**Summary: ** [Tony/Loki] Frostiron Month 08: They can keep up with one another. They are practically the same person split between two bodies. That's why they love one another. (But they hate each other too, because sometimes they hate themselves).

**Warnings: ** Slash. Loki/Tony. prompt: kinks. Loki needs a hug. Tony needs a hug. Good thing they have each other. No one else could manage them. Birds of a feather. Lots of drabbles. Feels. Angst.

**Rating: ** PG15.

**A/N**: Assortative mating, in human genetics, a form of non-random mating in which pair bonds are established on the basis of phenotype (observable characteristics, education, etc). This should not have been as long as it is…

_XXX_

**Words: ** 4,100

**Chapter 1**

**Clever.**

He was clever. He always had been. In school, in college, he'd been smarter than the teachers, and they had hated him for it.

He'd been smarter than his tutors and they'd hated him for it too. He had been smarter than Thor and everyone had hated him for that. They'd accused him of mocking the crown Prince, or being jealous and cheating and lying to look better than him; Frigga had been the only one to encourage him to stay smarter, to ignore their comments and work harder. Not to act dumb to appease the masses. So Loki had been clever.

Tony had worked hard to make his father proud of him, but it hadn't helped. He could be as smart as two Howards put together, but that still hadn't made him as good as Captain America, who, yeah had won a world war and could punch like a freight train but couldn't wrap his mind around quantum astrophysics. Pft. Loki had managed it after one explanation.

He was clever, though, and Tony was clever too. Smarter than most of the people they knew cramped together in one room, all of their brain cells merged into one, and it still wouldn't hold a candle to _them_.

**Tricky**

Some might call it cheating, but he called it smart. Sometimes it was best to admit that you couldn't win a fight fairly. He was only human after all; he couldn't stand up to some of the forces that were terrorising the Earth these days unless he cheated. So he cheated, because he was Iron Man and people were counting on him and he didn't like to lose. Cheating was all about being smarter than they guy you were playing, having a better poker face and lying through your fucking teeth. All of which, he could do.

Loki had centuries of practice at it under his belt. Thor had always been the easiest to trick, even now, his brother fell for all of the same-old tricks. It had been necessary at first, something to get him out of hopeless situations without causing himself irreparable damage. But he had been so good at it, too good at it in fact, and it became an addiction. He needed it more and more, the lies, and the danger, like an adrenaline rush until each scheme needed to be more and better and quicker because people were starting to see through them. But he got better, and quicker, and sneakier, and he learnt to use the truth as a lie and let people jump to their own conclusions so he was never truly at fault for his lies.

He had seen through every one of them though. The same as Loki saw through his, because they were both dirty, rotten sneaks at the core. But it was so much fun to team together against the rest of the Avengers, or their enemies, and watch them fall for the same pranks over and over again, Jarvis on their side and the others unable to prove a thing.

**Insane**

There was a madness in him, the kind that sprung from seeing things he had no right to see. Maybe it had always been there, festering, but witnessing the Void hadn't helped. Pepper would have said he'd always had a touch of it, Rhodey would have agreed; Happy wouldn't have, because he was paid to be loyal, but he would have thought it. There had always been madness in him, but Tony liked to think of it as eccentricities.

He was mad too. He always had been. The only difference between them here was that Loki knew it and admitted to it. Tony liked to pretend that he saved people to absolve his guilt, and yeah, he did, but he also carried nuclear bombs through worm holes and used his suit to protect other people while he was sucked to the bottom of the ocean by a crumbling mansion because there was some part of his brain that didn't work the way it should. Loki understood that, accepted it in fact. He was the same. Or he used to be: the times he had put Thor's safety ahead of his own, shoving him out of the path of raging Bilgesnipe or dragons and being injured for his kindness were long past, but now he injured himself to protect another. It was a madness all of its own, love. But he was insane in other ways as well.

A film had once said, "Some men just want to watch the world burn", and they thought it was rather apt. They'd be those men, other than the fact that they had always had someone to keep them grounded. Tony hadn't cared who got hurt as long as he made money (or as long as he was hurting himself) until Afghanistan, and then he hadn't cared who got hurt as long as _he_ was the one doing the hurting. He had killed people, and sometimes he felt guilty for it, so maybe he wasn't as insane as Loki, who had killed _more_ and couldn't care less.

It was the way of mad men. Loki had accepted that, that he was a God of Fire and Chaos as well as lies, and one day he'd burn the world (and the other eight of the nine). When the worlds began anew, he would burn them again and again for that was his destiny, and Loki revelled in it, instead of fighting against it because there was something in his brain that didn't work the way it was supposed to. Only thoughts of burning Tony kept him from starting Ragnarok too soon. But when Tony died...

Tony would destroy worlds to keep Loki safe if he had to. He'd told Asgard as much when they came calling, and that was madness too, but perhaps it was only mad because Odin had backed down.

**Paranoid**

It started as a nagging suspicion, because of something Thor had said. Loki had multiple copies of himself, each of them could move and act independently of another. Centuries ago, Loki had apparently also had multiples lovers, each one for a different clone. Now Tony knew his way around a bedroom and a naked body, but Loki was a God! Surely there were things he had done, felt, had done to that Tony couldn't possibly match, but the thought had never crossed his mind until Thor had joked about Loki using his clones in the bedroom. Because Loki hadn't. Tony couldn't help but wonder who else his clones were doing, if they weren't busy doing Tony?

Thor's stupid joke had made him narrow his eyes. The blond knew Loki had only done that because of a bet made against Fandral that he could bed more people than the Æsir Casanova could in half the time, and cheating was the only way for him to win. Loki had won, but he'd also had to put up with a dozen spurned lovers and a couple rather clingy bar wenches who thought having sex would mean they'd become a Princess of Asgard shortly after. Thor had known that it was one time, and that Loki generally didn't like having his clones in the bedroom because his lovers paid too much time on them and not on him. It started out well, his lovers were always excited, but by the ninth time of Loki alone not being good enough, the God had dumped them and moved on. He didn't want to move on from Tony Stark, but now the mortal had this look in his eyes that made Loki's narrow. Yet he never asked. They all asked, at some point after finding out that Loki could clone himself, after Fandral had spread the rumour to make up for not winning; they all asked, but Tony. Maybe, Loki thought suspiciously, he didn't ask because he didn't have the energy to keep up with all five of them? He was virile and spry for a mortal of his age, but maybe he had other people to exhaust him when Loki wasn't around?

They thought the worst of people, they always had. Not many people had ever given them a reason to think otherwise, at least not from the offset. Some people they had learnt to trust and to love, but none (bar their mothers) had they ever trusted instinctively. They were suspicious, but too proud to check; paranoid, but too suspicious to ask because why wouldn't the other lie? They were liars both.

**Creator**

He made machines and he gave them the ability to adapt and grow.

He made monsters. They had the ability to devour worlds.

They both created, out of a need to do so or out of boredom or just to prove that they could. Tony made his first robot out of loneliness, and his second out of desperation to prove that it wasn't a fluke; not that Howard cared either way. Loki created his first by mistake.

Fenrir had been the cub of a wolf that had attacked him when he was young. Loki had killed the wolf and one of her cubs and then discovered Fenrir huddled beneath some bushes, apparently not intending on attacking the mage like his kin had. The wolf had been sickly and small, like Loki was probably often thought to be, so Loki had scooped him up and taken him home. Baldur had killed him, 'rescuing' Loki in the process as he claimed, and left the cub's corpse on the streets of Asgard to rot when he dragged the younger Prince home. Loki had snuck out later that night, tears blinding him and half-moon marks of rage covering his palms, and he had hugged the small furry body close to his chest, Seiðr leaking out of him as he cried. Fenrir had howled, three hours later as the full moon reached its summit, and Loki had been so startled he had thrown the cub away from himself. The wolf had lived, and grown, and grown, and all knew that Loki was responsible for its hatred of everyone other than himself (and his mother).

Jarvis had been based off of an old man that had been more of a father to him than his actual father, but who was actually his butler growing up. Jarvis, the butler's, brain scans had been used, copied and uploaded, changed from matter to data and then given technological form. His voice was similar, but no sample that Tony had ever found came quite close enough. But Jarvis had the ability to adapt, and he change a little more of himself every week, re-writing his code until he suited him better and Tony never interfered. He changed his voice to sound more authentic British, like the real Jarvis', he changed his opinions to be less mirrors of Tony's and more his own, and he changed his likes and dislikes depending on how much certain people or things upset his creator. He played pranks on them (without Loki's interference or encouragement) because he disliked anyone who disliked Tony Stark on principle, and he enjoyed it. Tony allowed it, he even recommended other parts of code that could be changed or improved upon, other emotions that they could write into existence for Jarvis to experience. Not even when an AI built by a competing scientist attempted to take over the world did Tony ever stop to consider that maybe allowing Jarvis so much freedom was a bad thing; never would he consider such. He had created Jarvis, like he had Butterfingers, U and Dumm-E. They were his machines, his creations: his children.

Like Fenrir and Jormungandr (who had mutated after a rather bad plan involving Loki, the World Tree and a backfired shrinking spell cast at Thor, causing the snake to grow to eclipse the suns of Asgard) were Loki's children in the ways that counted. Like Hel was his little girl, monstrous as she appeared.

They were both creators and givers of life, fleshy matter or code notwithstanding. They were fathers of monsters both, as many as the other, and they were proud of that fact. Just because _their_ fathers hadn't been, didn't mean they wouldn't be proud of their children.

**Egotistical**

All publicity was good publicity! That was the saying right? Well, if not, it was the code he lived by. Crash your car off the side of the cliff your mansion is built on: that'll get your face on the front page of the newspaper. Drink drive and hit someone on the way home: huge lawsuit, but at least you'll be on the news. Get kidnapped by terrorists, escape and blow them all to Kingdom Come (capitals necessary to represent adequately how many explosions he used): stocks will plummet for a while, but then they'll crash through the roof! Marry the insane God who invaded the Earth with an alien army and decimated Manhattan: Tumblr _and_ Twitter will explode, but at least he'll be trending.

There had been a time when Loki had wanted the worlds to know his name, if only because they would worship him where Asgard wouldn't. That time had not ended yet, but momentarily he would settle for having Midgard cry his name in horror and protestation the way they had once chanted it in prayer. He had invaded them, terrorized them, and killed scores of them. Yet, they called him out on the internet, worshipped him from the comfort of their own homes through Macs and Vaios and Starkpads. They stood outside of Avengers Tower in scores, ranging between the ages of eight and eighty, alternatively crying out his name or Tony's, seeking attention. Fans posted photos taken (not so) subtly while Tony or Loki were picking up coffee or lunch of their faces with them in the background, unknowing until someone tagged them in the photo. He wasn't a God, per se, not in this modern Midgard, but he was their _god_ nonetheless; a god, of fame and fashion and Facebook.

Their wedding was ridiculously publicised. Tony all but built a Tower with Loki's name on the side, right beside his own, just to put the point across. In the end, he settled for hanging lights from the sides of the Tower, Loki's magic bending and twisting the strings so that it spelt out 'just married' and they flashed in time with the wedding march during the day and 'Back In Black' all through the night. It was flowers, and parades, and a monument built to the skies with their name plastered on it. It was everything they could ever need and more.

It still wasn't enough.

**Self**-**loathing**

He had wanted to save the world once.

As a child, watching his father build weapons, he had thought that peace was determined by the person with the biggest gun. Like the adage, he who makes the gold makes the rules, but with bullets and mines; the loser the one too stupid to back down from a fight he couldn't win. That had all changed eventually, not that Tony didn't still think the person with the biggest gun would win the fight, but that metaphorical gun had changed to magic and Extremis and Ultron. Things he could never have imagined as a child, nightmares that shouldn't have been given thought during his waking hours, and yet had become a normal part of his life. So Tony did as he always had, as Howard always had: he built bigger guns. Weapons that used arc technology, weapons that harnessed Loki's magic, and then some that crippled magic altogether, he made weapons that imitated Cerebro, using Jarvis instead of Charles to control it, he modified the Destroyer and sent it out to wage his wars. Stark Industries always had the best of the best to offer, but when it came to weapons, Tony Stark owned the only right to use them. Unfortunately, that meant whenever someone who shouldn't have got their hands on his weapons, the blood was on _his_ hands.

Loki had grown up on tales of heroes. The Warriors of Asgard, the elite few who fought alongside the Valkyries at the head of Bor's armies, marching on Jötunheimr and Vanaheimr and Svartalfheimr, and then later marching again for Odin. Loki had always wanted to be one. It was one of his earliest memories, swinging Thor's wooden toy sword around and declaring that one day he'd be an Einhärjar too (Thor had laughed at him and taken the sword away). As he had grown, Loki had learned that he was far better at destroying than he was at saving. So he had given up one dream, and nurtured another. His desire to rule and be worshipped was just as doomed to failure as his previous aspiration, but it took longer for Asgard to disillusion him of this one. When it happened, Jötunheimr threatened to implode, millions died without knowing why or how or what they had done for Laufey had already been killed by Loki and could not call them to war this time. Scores upon Midgard fell beneath Loki's army, as did most of the army.

As did friends, battle after battle as the years passed. Or they were lost to old age.

Tony hated himself sometimes because he had the blood of innocents on his hands, faces he didn't know and others he couldn't remember (except Yinsen who still haunted his dreams). He woke up screaming some nights, hands outstretched to draw someone back from whatever horrible fate had snatched them from him years ago, but they were always empty. He had never been able to save anyone when it really counted. A few kids here and there, a puppy once because Steve goaded him into it, but when it was Pepper, or Bruce, or Happy, Tony had always (would always be, every single night) been too late. It was survivor's guilt, Steve had told him once, the two of them and Natasha drinking vodka from the bottle in a circle around Clint's grave. They both had it too: genetically modified and unsure of when they would age or die, or even if they could.

Loki did not have that problem. He was long lived, a little less so perhaps than true Asgardians, but he was still welcome to the golden apples of Idunn and the healing magics of the golden halls. He would die faster than an Asgardian who had stopped eating the apples, but since he had no intention to stop any time soon he didn't concern himself with the thought. He and Thor both had long grown used to the knowledge that mortals died sooner than any other intelligent species in the realms. That was the real reason Odin had been so against Jane Foster. She would die and Thor would mourn her, for Odin would not let a mortal who questioned so much and so vocally become a citizen of Asgard lest she change them. It was why Loki had not bothered to tell the Allfather about Tony at all. Neither had he told Tony about the golden apple he had blended into their morning smoothie.

Tony hadn't noticed for a while. He took care of his body, exercised, ate well (occasionally), had cut out a lot of the drinking since Pepper and then Loki, and though he denied it smothered his face in anti-aging cream once a month before bed. It was only when Jane who had been refused citizenship and was going grey at the temples asked for Tony's 'secret' so that people would stop mistaking her for Thor's mother that he understood.

They had fought. It had been spiteful and bitter and violent. They had hated each other for a time, despite loving each other, because everything they did they did fiercely and their anger burned like dragon fire (Tony's for being tricked and Loki's for his trick not being appreciated), but they had come back together again. They were practically the same now, more so when Thor chose a mortal life to grow old with Jane, leaving Tony as the resident Asgardian member of the Avengers (since Loki refused to officially join them).

His friends had started dying, one by one, and Pepper had gotten sick so maybe it was fortunate that a Skrull had killed her before the cancer could, but that didn't make it hurt less. A bomb got Rhodey somewhere near the Iranian border; the Ten Rings gleefully took the credit. Happy died in a car crash, or rather, Tony pulled the plug on his life support after the car crash, his mind's eye not seeing the bed or the wires, but the last time they had been like this, Happy blown up by an Extremis-wired man-bomb with Tony helpless once more to help. Clint from old age mostly, but also liver failure. Bruce finally managed to find a way to kill the Hulk (completely by accident, so Tony blamed SHIELD because Bruce had been working for them at the time. There was no one left alive there he spoke to, and it wouldn't make Bruce any less dead, so he drank himself unconscious and let it go). He hated himself for it. Steve was still there, and Natasha, but they had long quit the Avengers. They were a trio of former heroes and borderline alcoholics (and maybe suicidal thrill seekers, but what didn't kill them made them stronger and made them want to drink more so whatever).

Eventually, he brought Tony to Asgard with him. Loki allowed the mortal to watch the super-soldiers die, one in childbirth of all things and the other of a heart attack once someone managed to reverse engineer Erskine's serum. Like some mutants had jumped at the chance of having their powers removed, Steve had lived long enough to want a normal life before he died. He hadn't expected to die two days later, while drinking coffee with Tony in Central Park. Natasha had taken the formula too, gotten pregnant and wanted to keep the baby. The doctors had been Hydra agents and they had let her bleed to death after they cut the child from her too early. Bucky Barnes was long gone, replaced once more by the Winter Soldier, and he watched them die with furrowed eyebrows in cold silence. Loki had watched them too, but he hadn't helped or healed or protected. Because he was better at destroying. The longer he allowed Tony to remain on Midgard, the more he destroyed him.

Each death tore a hole in him that Loki couldn't fill. Each new face, new acquaintance was kept at arm's length because of each death that had come before. Tony hated himself for not being able to save them, for living when they couldn't. Sometimes he hated Loki for taking the choice away from him, but then Loki would look at him, green eyes wide and mouth tight, hating himself though he would never admit to remorse and the anger would leave him. Tony would just be tired and angry with himself for not seeing it sooner, soon enough to share immortality with the others, to beg Loki for another apple or two. It was too late now, and he was too late as always, and he had eternity to hate himself for it (more than he already had before) because now there were new crimes and new blood to add to his hands.

Loki hated himself sometimes too. Not because he had killed people or failed to save people. But because sometimes when Tony looked at him, the God knew that Tony wished he had let him die too.

_XXX_

They were two completely different people, but they fit together so well. One always seemed to compliment the other, even during arguments; they were occasional-opposites that attracted as they fought. Neither ever won unless they resorted to cheating, which both did from time to time, or used dirty, rotten tricks to distract the other. They were so different, the other Avengers couldn't understand how they worked so well together, how they could still be happily (intermittent with earth trembling spats and bed breaking make up sex) married even after the more human of the Avengers had died of old age.

Tony lived in Asgard with Loki after the rest of the Avengers had passed. Then it was Asgard's turn to wonder how they could be so different and so perfectly similar at the same time.

Sometimes, different people are the same. And phenotypes attract.

**The End**


End file.
